Eccentric ring impacting mechanism for in-situ rock breakers

ABSTRACT

There is disclosed a mechanically driven impact rock fracturing mechanism having a rotary eccentric shaft drive. An impact member in the form of a ring is rotatably mounted on the eccentric shaft and driven in an orbital path to intermittently engage a fracturing shank. Means are provided including a reaction ring to constrain the ring impact member to rotate with respect to the eccentric shaft.

nite States Patent [191 Cobb et a1.

[451 Feb. 25, 1975 ECCENTRIC RING IMPACTING MECHANISM FOR lN-SITU ROCK BREAKERS [75] Inventors: Delwin Earl Cobb; Jerry Dale Fidler, both of Peoria; Nathan Gutman, Washington; Richard Edward Livesay, Peoria; Orrin Arthur Stemler, Metamora, all of Ill.

[73] Assignee: Caterpillar Tractor Co., Peoria, 111.

[221 Filed: Aug. 23, 1973 [21] Appl. No.: 390,911

[52] U.S. Cl 299/37, 37/D1G. 18, 172/40,

173/98, 299/70 [51] Int. Cl. E21c 27/28 [58] Field of Search 299/37, 69, 70, 67;

37/D1G. 18, 141 R, 141 T; 172/40; 173/98 [56] References Cited UNITED STATES PATENTS 7 1,464,570 8/1923 Hage 173/98 3,448,535 6/1969 Haynes ..37/141R 3,512,284 5/1970 Haynes 37/141 R Primary ExaminerErnest R. Purser Attorney, Agent, or FirmPhillps, Moore, Weissenberger, Lempia & Strabala [57] ABSTRACT There is disclosed a mechanically driven impact rock fracturing mechanism having a rotary eccentric shaft drive. An impact member in the form of a ring is rotatably mounted on the eccentric shaft and drivenin an orbital path to intermittently engage a fracturing shank. Means are provided including a reaction ring to constrain the ring impact member to rotate with respect to the eccentric shaft.

14 Claims, 6 Drawing Figures ECCENTRIC RING IMPACTING MECHANISM FOR IN-SITU ROCK BREAKERS,

BACKGROUND OF THE INVENTION The present invention relates to rock fracturing implements and pertains more particularly to mechanically actuated impact apparatus for rock breaking or fracturing.

Numerous techniques for breaking rock formations and the like for mining, excavation, and demolition are available. Blasting with high explosives is a common technique but cannot be used near population centers.

Mechanical impact apparatus such as the pneumatically and hydraulically driven jackhammers can be used around cities, but also have some drawbacks. Other mechanically driven apparatus such as crank drive are known but also have some drawbacks.

Proposals to mount impact rock breaking devices on the outer end of an excavator boom have been made to reach remote and difficult to reach situations. The prior art is exemplified by the following patents:

US Pat. No. 3,027,027 issued to M.J. Bles on Mar.

US. Pat. No. 3,328,904 issued to W.D. Voigt, et al.,

on July 4, 1967;

US. Pat. No. 3,512,284 issued to F.J. Haynes on May 19, 1970;

U8. Pat. No. 3,645,021 issued to J.T. Sonerud on Feb. 29, 1972;

US. Pat. No. 3,677,604 issued to PJ. Leyrat on July 18, 1972;

US. Pat. No. 3,729,056 issued to F.W. Paurat on Apr. 24, I973.

One problem with such prior art devices is that they are bulky and are limited in their power and maneuverability. Thepresent invention is directed to an improved impact drive apparatus for such rock breaking apparatus. It also represents an improvement over the general type impact drive mechanism of co-pending application, Scr. No. l33,262, filed Apr. 12, I971, and assigned to the assignee of the present invention.

SUMMARY AND OBJECTS OF THE INVENTION It is a primary object of the present invention to provide a simple and rugged impact mechanism for rock fracturing devices.

It is another object of the invention to provide a compact and ruggedmechanically driven impact mechanism for a rock fracturing machine.

In accordance with the present invention, there is provided a mechanically driven impact device that utilizes an orbiting mass having multiple impact surfaces for impacting a ripper shank. Means are provided to rotate the impact mass about an axis that is offset from the orbit axis.

BRIEF DESCRIPTION OF THE DRAWINGS The above and other objects andadvantages of the present invcntionwill become apparent from the following description when read in conjunction with the accompanying drawings wherein:

FIG. I is an elevational view of an apparatus in accordance with the present inventionmounted on the boom of an excavator machine;

FIG. 2 is an elevational view partially in section of a preferred embodiment of the present invention;

travel of a point on the impact face of the impact mem-' ber of the embodiment of FIG. 2; and,

FIG. 6 is an enlarged viewofa portion ofthe diagram,

of FIG. 5.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS Referring now to the drawings and particularly to FIG. I, there is illustrated an impact fracturing apparatus in accordance with the present invention shown mounted on the outer end of the boom of a hydraulic excavator. The impact fracturing apparatus generally designated by the numeral 10 is mounted on the outer end of the linkage of an excavator generally designated by the numeral 12. The excavator is the usual type comprising an undercarriage 14, a rotatable upper structure 16 that is rotatable 360 around the vertical axis through the undercarriage. The upper structure hasconnected thereto the usual bucket linkage assembly generally comprising a boom 18, a stick 20, and the usual bucket tilt linkage 22 at the outer end of the stick. These linkages are manipulated in a known manner by suitable hydraulically-powered jacks or motors 24, 26, 28 respectively.

The impact fracturing apparatus 10 as illustrated is. designed to be fitted to the linkage when the bucket is removed and comprises generally a base member 30 to which is rotatably mounted a housing 32 containing the internal structure of the apparatus to be described. The

housing 32 is secured by means of a swivel joint ar- I rangernent 34 including hydraulic driving means for ro tating the housing portion 32, preferably 360 about its axis with respect to the base member 30. g

This arrangement of the impact fracturing apparatus in combination with the excavator and its linkage provides an extremely versatile machine which may be used in a number of situations such as illustrated wherein it is impossible to reach by other machines. The compact and slim profile arrangement of the impact fracturing apparatus itself permits the apparatus to, develop and. introduce very high rates of energy into remote and close quarters. The pivotal support of the linkage as well as the rotatable swivel arrangement 34 permits the manipulation of the impact apparatus to situations that are otherwise very hard to reach for excavating and for demolishing work. As shown in phantom in FIG. 1, the linkage may be used to present the apparatus as shown in the uppermost position to work against the face of a wall or cliff as shown that cannot otherwise be reached by conventional means.

The internal mechanism of the rock fracturing apparatus stores and delivers high levels of energy by impact to a fracturing shank 36 pivotally secured or mounted to the housing 32 and includes a fracturing tip or point 38 for engaging and fracturing rock and like materials.

Referring now more specifically to FIG. 2, there is illustrated in detail a preferred embodiment of the apparatus in accordance with the invention for developing and delivering high levels of energy by impact to a rock fracturing tool.

The housing 32 encloses the major moving components of the impact mechanism of the present invention [face 80a of the impactreceivingmember As seen in the illustratedembodiment, the impactyre-Y ceiving member sfl extendsin'to the interiorot the housing 32 via asuitable opetiingj861withfthearea' bef. f} tween theop eningand member 80 appropriately sealed by means of a suitable annular inflatabieseal 88 which wearing motiontofthe memberstf I a I r i v i Asthc ringmcmber filltntoves aboutin o'rbit'al fash ion within the housing it intermittentlyfimpacts against" Q the member, 8% and drives the shank outwardly with the; I tip'3h the rcolpointed in thedirection of motio'mAs the 7 V and includes an annular wallI tUconnectinganupper gwall 42am alower removable wallY-M The lower wall member Mispreferably detachable andis secured in, place inpthe usual manner; by boltsjasshown at 46. V

A main drive shaft 48 is ,journaleclinthehousing in bores 50 and fil formed in walls 42' and why-means bearings 62. Suitable thrust,washersarefarranged'at 64 ot suitablebearing means Stand 56. The shaft48 incluldes an eccentric 58 on which is rotatably journaied an impact member 60 by means of' suitable journal and 66 to allow relative rotation between the'i mpact member 60;and a pair of flywheels. 68uand70 which are! 1 h suitably keyed such aszsplines 72 and 74 to ma indrive i, a shaft 48. Suitable thrust bearings vegan 7,8 are p victed between the ends of the'respective fly wheelsend the, housing members 42 and 44;The flywheels together with the drive shaft and eccentric means are" constructed and arrangedto form a nta ssivebalanced flyvvheelsystem for storing largeamount-s ofen'ergy for); 'deliveringto the shank. i :"The impactpmember 60 isinthe form of aniannular ring member and is essentially driven or 'movedlin an orbital path within thehousingv around the eccentric 58 a V 'ofthedrive shaft 48. The impact me'mberfiil impacts against ant im pact receivingmember which; in' theii illustrated embodiment, is appropriately securedras b y a suitable sofcket 82 which receives a pin 840i? the ripe- U per shank 36 to secure the impact receiving member 80 r V to the rippershank/The impactr'eceiving mernber'IBG is in'ess'en ce a replaceable wearcapQTihe ripper tip 381 generallypoints in a direction away front'theintpact pactt'mernber60.1} g l V g patterntracedby a point'on the permits reciprocal moiton of the impact receivingmember 80 and the shank .tnember fiflThe,seal mem- '92'to-the impact receiving member 80. Once utheiseal "and thus providesan effective seal withoutslidingfor tip 38 moves-forward under the impact of the ring member 60, the reaction of the' rock against'the tip will Also ofimportanc'einconsiderat 'One considerationvin developing this factor is the dif eferences in diameter betweenthe pinion gear and thei cause the tip to move backwards, or rebound. In order be or too fast and possibly damage the impact ring or the portionsof the impact mechanism, a dampingdevice t 94 is provided. This damping device absorbs and restrains the shock of the shank and allows it to move backward only a'predetermined distance. The'restriction of the backward movement of the shank also prevents the ringfrom impacting the shank except in the i move more generally along the axis of movement of the desired location of the rings orbiting path. The shock damper can be provided with any suitable typeofinter f toQlOS the impact ring will contain; r With a" ge ari dif ferent gear iratiog eithe nal camping means incliidinglfntechanical,ihydraulic and'pneumatie.

The annular 'impact tnember en hasianvoitter substan i a t t tially cylindrical impact faceitilitrwhich essentially dey r 'finesa plurality or an infiniteniirnber; ofimpactfaces for engage men'tiwiththe impact receiving member 8t Slidihg frictio'n between 5 this face i and; the {impactn receiving memberhil canhereclucedjor minimized by contourof the back siifrface'of the impact receiving* memberr Additionallygtheiifeof the ringfi an be substantially increased by providing a;pluralityu of,impact a, surfacesi This]is accompiishedjby constraining the r a memberto rotate ebont its axis as itiswntovedlor driven V aboutits orbitr In theillustrated embodiment this isac- T complishedby providingastationary reaction 96 I which comprises/a ring gearand isse'cured, in a suitable a manner SHChifQS, byiboltsl98 to t'hej hohsi ngqwall 4G,.A 1

drive member preferablyinithe formiof a pinion gear; '100issecriredi preferably by meansofsuiteble elastic f means 102 tome impact member, lillandengages the I a i 7 ring gearf96 to thereby drive the impactmentbet 60 in. V i a rotary mannerfasit isfjnoved ondriY'eninyitsorbital I path with in the housing} Thisjxgearconnectioncon" by strains the impactmember to rotateaabont the axis 'offthe eccentricjnember 58 which isparallel to and'offa set fromthe driveaitis of dl'iVElSi'hQfL48i; M

i a This connection'makes the impact ring; membcr'o tl j "1 walkaroundfthe--housing:in 'a continuousiorcounter Q a a clockwise direction as"the gcrankfishaft 48 tel-mated in aclockwise direction.'The'bimpactisurfaeesor number: "thereofonitheface 68fis de'terrnin'ed bythe gearmno t between-the.gearllm andthe ring 96Theexactl'nnm f e bier offlirn pactlsnrfaces or facesican fbe predetermined by arranging theiprope mane of gearfteethQTheiratio i of gear teeth of'the'pinion 1100 tojithegear teeth ori ring 96 determinesithe, nt m berofimpact areas "on the'im FIG: 5 illu rates a I I g I periphery of the 'imp'aetlme'mber 60 was particular ber hfiflis appropriateiy secured to the respectivemem j 4 bets such'as'by' bolts 9 1 ftojthe honsing andiby clamp geariteeth ratio. The ratiooffldteet on "thezimpact "'lrin g QfldTlQStEtthCitflillhe housing-producethisparticu v s lar"patternfAnalysis oif'this pattern'shows'thataepartici ul'ar point =I04 will1t race the illustrated pattern ,before Im i ent the a a tsitp an pe n when tithes; Thismeans 't atpwith fthegiven ge the impactzniember with the impact I member' as it engages the impact-receiving member.

diameterof the impact member itself; Bytchanging the diameter of theimp'actyface '60a'with respect to thev the pattern of movernent'of'a point on the face6 0a to shank or rnember80 during the impactLThis movement insures a greater delivery of energy directly along the desired, direction as well aseliminates or reduces scuff? ing between the twoimpact membersiTheloop config nrati on as showniin FIG-S.5 and b inade by the, point 7 pact-recelving member {80146 a ratioof liQ mpact areas;

a n m j it isthedirectionofEmGvernent'ofthe face'oftheimpact, jg I 4 is the result of the, diameter of member 60 being less than the pitch diameter of the pinion :gear 100.

Referring now to FIG. '4, there is illustrated a slightly modified version of the apparatus wherein the means to constrain the impact member to rotate as it moves about its orbit comprises a frictional drive means. In this embodiment, identical elementsare identified by the identical number and slightly modified elements are identified by the number primed, thus the impact member or ring is 60and is formed with tapered surfaces 106 and 108 to respectively engage a pair of frictional reaction rings 110 and 112. The frictional reaction rings 110 and 112 comprise spring washers with a tapered concave face serving as the frictional engaging surfaces. in this embodiment as the impact member 60' is driven in its eccentric path, it is constrained to rotate by means of thefrictional means; When the impact member strikes the shank or impact receiving member, it will slip or slide slightly along the frictional connection. As with the previous arrangement, a plurality of impact areas are provided on the impact ring. However, since the connection is of the friction type, the exact number of impact areas is not discernible and there will be no definite repeatable pattern of the impact areas.

Reference to FIGS. 5 and 6, the diagrams, illustrate the results achieved by providing a proper ratio of diameters of the driving means and the impact member: By selecting the impact member diameter with a smaller diameter than the diameter of the gear ring, the loop configuration movement of a point on the surface of the impact member is achieved as shown in FIGS. With this arrangement the point on the impact surface can be said to be moving approximately parallel with the line of reciprocation of the impact receiving member upon impact. This point of impact is illustrated in FIG. 6 asthe peak indicated at 114. This path of motion results in a sharp impact acting along the line of movement of the impact receiving member 80 and which results in less scuffing ata the point of impact. It also results in a maximum transfer of energy from the impact member to the impact receiving member.

The above described arrangement provides a rugged and compact impact fracturing mechanism wherein very high levels of energy can be transmitted directly from the eccentric crank shaft and to the fracturing shank without loss of energy in the coupling therebetween. The particular ring impact typeconstruction provides a more rugged construction than conventional crank and link mechanisms and provides a longer life for the mechanism as well as a more compact arrangement. 7

While the present invention has been described with respect to specific embodiments, it is to be understood that numerous changes and modifications can be made therein without departing from the spirit and scope of the invention as defined in the appended claims.

What is claimed is:

1. An impact mechanism for delivering intermittent impact blows to a rock fracturing shank comprising:

a housing;

a drive shaft having an eccentric journal rotatably mounted in said housing;

a fracturing shank reciprocably mounted adjacent said housing and having an impact receiving member extending into said housing and a fracturing tip extending away from the impact receiving member;

an annular impact member having a plurality of impact faces rotatably mountedin said housing on said eccentric journal and driven by said shaft in orbital path for intermittent engagement of said impact faces with said impact receiving member; and,

means for constraining said impact member to rotate about its axis in a direction opposite the direction. of rotation of said driven shaft when driven in said.

orbital path.

2. An impact mechanism for delivering intermittent impact blows to a rock fracturing shank comprising:

a housing;

a drive shaft having an eccentric journal rotatably mounted in said housing;

a fracturing shank reciprocably mounted adjacent said housing and having an impact receiving member extending into said housing and a fracturing tip extending away from the impact receiving member; and,

an annular impact member having an outer cylindrical surface defining a plurality of impact faces mounted in said housing and rotatably driven by said eccentric journal of said shaft in orbital path for intermittent engagement of said impact faces with said impact receiving member;

constraining means comprising a stationary reaction ring mounted in said housing concentric to said or bital path for constraining said impact member to rotate when driven in said orbital path; and,

drive means carried by said impact member for engaging said. reaction ring.

3. The impact mechanism of claim 2 wherein said reaction ring is a ring gear; and,

said drive means is a pinion gear secured to said impact member.

4. The impact mechanism of claim 3 wherein at least one of said ring gear and said pinion gear is secured to one of said housing and impact member by resilient means.

5. The impact mechanism of claim 3 wherein the pitch diameter of said pinion gear is different from the outer diameter of said impact member.

6. The impact mechanism of claim 5 wherein said pitch diameter is greater than said outer diameter.

7. The impact mechanism of claim 5 wherein said pitch diameter is less than said outer diameter.

8. The impact mechanism of claim 2 wherein said reaction ring includes a friction drive surface; and, 1

said drive means is an annular friction surface carried by said impact member for frictionally engaging said friction drive surface. 9. The impact mechanism of claim 8 wherein the pitch diameter of said annular drive member is greater ber extending into said housing and a fracturingltip V faces with said impact receiving member; and

umeans for rotating said impact member cou'nter to the rotation of said drive shaft so that a point on said impact face defines a loQp during movement H tloivard and away frpm saidximp act receivingrn'emv 113Q-An impact mech anism forrdeii xering intermittent impact blows to a rock fracturing shank comprising: 7 a'housing;

a driv'eshaft' having an eccentric journal rotatabiy 'mounted in saidh ou sing 21 fracturing shankrreciproeably mounted adjacent 3 said housing. and havingan impact receiving niemberex t'ending into saidhousing anda fracturing, tip extending away frorn the irnpact receiving member; f

reacticm ringis a ringrigear; and;

means'for rotating said impact membercornprising a ireaet ion tijing disposed adjggenr 7 from said impact receiving member, 'saidannular 'drive jmemberhavi 1 diameter 6fsidf-impaet;faee. V 14, The impact,mechanismwofciaim i io ian q; pzith, andan; V annular drive member carriedi y s id impact rnem-n f'ber forengzig'ing said reaction ring fdr constraining saidirnpacrrnemberto rdiatewhen driven in said Orbitai' path, sdth'at ipoint on said impact face tie; i fines a loop during movenren t to ward and aWaY f g a diarrietergreater than {he wherein said; 

1. An impact mechanism for delivering intermittent impact blows to a rock fracturing shank comprising: a housing; a drive shaft having an eccentric journal rotatably mounted in said housing; a fracturing shank reciprocably mounted adjacent said housing and having an impact receiving member extending into said housing and a fracturing tip extending away from the impact receiving member; an annular impact member having a plurality of impact faces rotatably mounted in said housing on said eccentric journal and driven by said shaft in orbital path for intermittent engagement of said impact faces with said impact receiving member; and, means for constraining said impact member to rotate about its axis in a direction opposite the direction of rotation of said driven shaft when driven in said orbital path.
 2. An impact mechanism for delivering intermittent impact blows to a rock fracturing shank comprising: a housing; a drive shaft having an eccentric journal rotatably mounted in said housing; a fracturing shank reciprocably mounted adjacent said housing and having an impact receiving member extending into said housing and a fracturing tip extending away from the impact receiving member; and, an annular impact member having an outer cylindrical surface defining a plurality of impact faces mounted in said housing and rotatably driven by said eccentric journal of said shaft in orbital path for intermittent engagement of said impact faces with said impact receiving member; constraining means comprising a stationary reaction ring mounted in said housing concentric to said orbital path for constraining said impact member to rotate when driven in said orbital path; and, drive means carried by said impact member for engaging said reaction ring.
 3. The impact mechanism of claim 2 wherein said reaction ring is a ring gear; and, said drive means is a pinion gear secured to said impact member.
 4. The impact mechanism of claim 3 wherein at least one of said ring gear and said pinion gear is secured to one of said housing and impact member by resilient means.
 5. The impact mechanism of claim 3 wherein the pitch diameter of said pinion gear is different from the outer diameter of said impact member.
 6. The impact mechanism of claim 5 wherein said pitch diameter is greater than said outer diameter.
 7. The impact mechanism of claim 5 wherein said pitch diameter is less than said outer diameter.
 8. The impact mechanism of claim 2 wherein said reaction ring includes a friction drive surface; and, said drive means is an annular friction surface carried by said impact member for frictionally engaging said friction drive surface.
 9. The impact mechanism of claim 8 wherein the pitch diameter of said annular drive member is greater than the diameter of said impact member.
 10. The impact mechanism of claim 8 wherein the pitch diameter of said annular drive member is less than the diameter of said impact member.
 11. The impact mechanism of claim 8 wherein said friction surfaces define a frusto-conical configuration.
 12. An impact mechanism for delivering intermittent impact blows to a rock fracturing shank comprising: a housing; a drive shaft having an eccentric journal rotatably mounted in said housing; a fracturing shank reciprocably mounted adjacent said housing and having an impact receiving member extending into said housing and a fracturing tip extending away from the impact receiving member; an annular impact member having an outer cylindrical surface defining a plurality of impact faces mounted in said housing and rotatably driven by said eccentric journal of said shaft in an orbital path for intermittent engagement of said impact faces with said impact receiving member; and means for rotating said impact member counter to the rotation of said drive shaft so that a point on said impact face defines a loop during movement toward and away from said impact receiving member.
 13. An impact mechanism for delivering intermittent impact blows to a rock fracturing shank comprising: a housing; a drive shaft having an eccentric journal rotatably mounted in said housing; a fracturing shank reciprocably mounted adjacent said housing and having an impact receiving member extending into said housing and a fracturing tip extending away from the impact receiving member; an annular impact member having an outer cylindrical surface defining a plurality of impact faces mounted in said housing and rotatably driven by said eccentric journal of said shaft in an orbital path for intermittent engagement of said impact faces with said impact receiving member; and means for rotating said impact member comprising a reaction ring disposed adjacent said path, and an annular drive member carried by said impact member for engaging said reaction ring for constraining said impact member to rotate when driven in said orbital path so that a point on said impact face defines a loop during movement toward and away from said impact receiving member, said annular drive member having a diameter greater than the diameter of said impact face.
 14. The impact mechanism of claim 13 wherein said reaction ring is a ring gear; and, said drive member is a pinion gear. 